Trained dogs and handlers will roam through the gate areas on the departure level of each terminal and visit with passengers awaiting flights while providing comfort and offering airport information, the airport said. Each volunteer underwent classroom and in-terminal training to learn about the airport and how to assist passengers.

PUP was launched earlier this week in honor of the upcoming National Volunteer Week (April 21-27). But the dogs are expected to be a fixture at LAX long after the week of volunteering comes to an end.

"We are pleased to launch the PUP program during in honor of National Volunteer Week," Los Angeles World Airports Executive Director Gina Marie Lindsey said. "It's a great opportunity to spread happiness to millions of travelers from all over the world. Expect to see the PUP's on a regular basis in Terminals at LAX."

All the dogs roaming the airport as part of this program are registered with Therapy Dogs Inc. of Cheyenne, Wyo. The nonprofit organization provides comfort and stress relief at facilities such as hospitals, schools, senior homes and other institutions.